1. Field of the Invention
The present invention relates to a cleaning apparatus for removing matters adhered to a member to be cleaned, and an electrophotographic image forming apparatus having such a cleaning apparatus. The member to be cleaned may be an electrophotographic photosensitive member, a transfer drum or a fixing roller, for example. Further, the electrophotographic image forming apparatus serves to form an image on a recording medium by using electrophotographic process and may be an electrophotographic copying machine, an electrophotographic printer, an electrophotographic facsimile machine or an electrophotographic word processor, for example.
2. Related Background Art
Now, a construction of a cleaning apparatus considered during the creation of the present invention will be explained with reference to FIGS. 10 and 11. Incidentally, FIG. 10 is a cross-sectional view of a cleaning apparatus, and FIG. 11 is a side view of the cleaning apparatus. However, the construction shown in FIGS. 10 and 11 is considered in the course of creation of the present invention and is not already known.
In the illustrated example, the cleaning apparatus 100 is disposed in the proximity of a transfer drum (member to be cleaned) 30 rotated in a clockwise direction (shown by the arrow) to remove and collect waste toner adhered to the surface of the transfer drum 30. The cleaning apparatus 100 has a rotary brush 2 disposed in parallel with a rotary shaft (not shown) of the transfer drum 30, i.e. along an axial direction (perpendicular to the plane of FIG. 10) of the transfer drum 30 as shown in FIGS. 10 and 11. The rotary brush 2 is rotatably supported by a brush case 3 which is in turn slidably supported by a slide plate 4.. That is to say, the rotary brush 2 is constituted by brush fibers 2a provided on a peripheral surface of a rotary shaft 5 rotatably supported by the brush case 3 at both ends.
As shown in FIG. 10, slots 4a extending in a left-and-right direction in FIG. 2 (direction that the brush case 3 is shifted toward and away from the transfer drum 30) are formed on a bottom surface of the slide plate 4. Slide posts protruding from a bottom surface of the brush case 3 are slidably fitted into the respective slots 4a. Thus, as mentioned above, the brush case 3 is supported by the slide plate 4 for relative shifting movement in the left-and-right direction in FIG. 10 with respect to the slide plate 4. The brush case 4 is biased toward the transfer drum 30 (left in FIG. 10 or 11) by two springs 11 (FIG. 11) disposed between the brush case 3 and the slide plate 4 on both sides of the brush case. Incidentally, one end of each spring 11 is connected to a spring attachment portion 3a formed on the brush case 3 and the other end of the spring is connected to a spring attachment portion 4b formed on the slide plate 4.
The slide plate 4 is slidably supported by a bottom plate 13 secured to a frame of an image forming apparatus via slide stop plates 12 provided on both sides of the slide plate. That is to say, as shown in FIG. 11, upper and lower slots 4c extending in the left-and-right direction in FIG. 2 (direction that the rotary brush 2 is shifted toward and away from the transfer drum 30) are formed in side walls of the slide plate 4, respectively, and slide shafts 14 extending horizontally an inwardly from the slide stop plate 12 are slidably fitted in the corresponding slots 4c.
Accordingly, as mentioned above, the slide plate 4 is slidable with respect to the bottom plate 13. As shown in FIG. 11, slide return springs 15 are provided between the slide plate 4 and the bottom plate 13 on both sides of the slide plate. The slide plate 4 is biased away from the transfer drum 30 (toward right in FIG. 11) by the return springs 15 until urging portions 4d of the slide plate abut against urging cams 16. In this condition, the brush 2 is separated from the transfer drum 30. Incidentally, each urging cam 16 comprises a disc-shaped eccentric cam a cam shaft 17 of which is driven by a drive means M.
On the other hand, as shown in FIG. 10, the brush case 3 is provided at its one end with an opening 3p facing the transfer drum 30, and the rotary brush 2 is disposed within the opening 3p. First and second scrapers 18 and 19 are formed on the brush case 3 above and below the rotary brush 2, respectively. The first scraper 18 has a scraper blade 18a, and the second scraper 19 has a scraper blade (suction guide) 19a and a blow preventing seal plate 19b.
Further, a filter housing 20 is removably mounted within a rear opening 3q of the brush case 3, and a toner scattering member 21 is disposed at an intermediate portion 3r of the brush case 3 (portion between the rotary brush 2 and the filter housing 20). The filter housing 20 has a filter 22 and an end filter 23 attached to a rear opening of the filter housing.
In a non-cleaning condition, the rotary brush 2 is not rotated and is separated from the transfer drum 30. In this condition, the transfer drum 30 is not cleaned.
The present invention relates to the improvement in the above-mentioned technique.